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Lead Zodiac Leo “Lion” Token
Lead 19mm (5.35 grams) Circa 50-200 A.D.
Lion leaping right; above, radiate and draped bust of Helios; thunderbolt below
within incuse countermark.
* Numismatic Note: The the lion looks like reverse type
of one of the the Zodiac series coins of Antoninus Pius of Alexandria Egypt. One
can explain this type to have been made for the renewal of the Great Sothic
cycle, the point when the star Sothis (Sirius) rises on the same point on
the horizon as the sun. This cycle of 1461 years began early in the reign of
Pius in AD 139, and apparently prompted a renewal in the ancient Egyptian
religion.
You are bidding on the exact item pictured,
provided with a Certificate of Authenticity and Lifetime Guarantee of
Authenticity.
The Sothic cycle or Canicular period is a period of 1,461
ancient Egyptian
years (of 365 days each) or
1,460
Julian
years (averaging 365.25 days each).
During a Sothic cycle, the 365-day year loses enough time that the start of the
year once again coincides with the
heliacal rising
of the star
Sirius
(the
Latinized
name for
Greek
Σείριος, a star called
Sopdet
by the Egyptians, in Greek transcribed
as Sothis
; a single year between heliacal risings
of Sothis is a Sothic year). This rising occurred within a month or so of
the beginning of the Nile
flood, and was a matter of primary
importance to this
agricultural
society. It is believed that
Ancient Egyptians followed both a 365-day civil calendar and a lunar religious
calendar.
Mechanics and
discovery
The ancient Egyptian civil year was 365 days long, and apparently did not
have any
intercalary
days added to keep it in alignment
with the Sothic year, a kind of
sidereal year
. Normally, a sidereal year is
considered to be 365.25636 days long, but that only applies to stars on the
ecliptic
, or the apparent path of the
Sun.
Because Sirius lies ~40˚ below the ecliptic, the wobbling of the celestial
equator and hence of the horizon at the latitude of Egypt, as well as the proper
motion of the star, causes the Sothic year to be slightly smaller. Indeed, it is
almost exactly 365.25 days long, the average number of days in a Julian year.
This cycle was first noticed by
Eduard Meyer
in 1904, who then carefully combed
known Egyptian inscriptions and written materials to find any mention of the
calendar dates when Sirius rose. He found six of them, on which the dates of
much of the
conventional Egyptian chronology
are based. A
heliacal rise of Sirius was recorded by
Censorinus
as having happened on the Egyptian
New Year’s Day, between AD 139 and 142. The record actually refers to July 21 of
140 AD but is astronomically calculated as a definite July 20 of 139 AD. This
correlates the Egyptian calendar to the Julian calendar. Leap day occurs in 140
AD, and so the new year, Thoth 1, is July 20 in 139 AD but it is July 19
in 140-142 AD. Thus he was able to compare the day on which Sothis rose in the
Egyptian calendar to the day on which Sothis ought to have risen in the Julian
calendar, count the number of intercalary days needed, and determine how many
years were between the beginning of a cycle and the observation. One also needs
to know the place of observation, since the latitude of the observation changes
the day when the heliacal rising of Sirius occurs, and mislocating an
observation can potentially change the resulting chronology by several decades.
Meyer concluded from an ivory tablet from the reign of
Djer that the Egyptian civil calendar was created in
4241 BC
, a date that appears in a number of old
books. But research and discoveries have since shown that the
first dynasty of Egypt
did not begin before c.3100
BC, and the claim that 4241 BC (July 19) is the “earliest fixed date”
has since been discredited. Most scholars either move the observation upon which
he based this forward by one cycle of Sothis to 2781 (July 19), or reject the
assumption that the document in question indicates a rise of Sothis at all.
Chronological
interpretation
Three specific observations of the heliacal rise of Sirius are extremely
important for Egyptian chronology. The first is the aforementioned ivory tablet
from the reign of Djer
which supposedly indicates the beginning
of a Sothic cycle, the rising of Sothis on the same day as the new year. If this
does indicate the beginning of a Sothic cycle, it must date to about 2773 BC
(July 17). However, this date is too late for Djer’s reign, so many scholars
believe that it indicates a correlation between the rising of Sothis and the
lunar calendar, instead of the solar calendar, which would render the tablet
essentially devoid of chronological value.
The second observation is clearly a reference to a heliacal rising, and is
believed to date to the seventh year of
Senusret III
. This observation was almost
certainly made at
Itj-Tawy
, the Twelfth Dynasty capital, which
would date the Twelfth Dynasty from 1963 to 1786 BC. The Ramses (Turin) Papyrus
Canon says 213 years (1991-1778 BC), Richard Parker reduces it to 206 years
(1991-1785 BC), based on July 17 of 1872 BC as the Sothic date (120th year of
12th dynasty, a drift of 30 leap days). Prior to Parker’s investigation of lunar
dates the 12th dynasty was placed as 213 years of 2007-1794 BC perceiving the
date as July 21 of 1888 BC as the 120th year, and then as 2003-1790 BC
perceiving the date as July 20 of 1884 BC as the 120th year.
The third observation was in the reign of
Amenhotep I
, and, assuming it was made in
Thebes, dates his reign between 1525 and 1504 BC. If made in Memphis, Heliopolis,
or some other Delta site instead, as a minority of scholars still argue, the
entire chronology of the Eighteenth dynasty needs to be expanded by some 20
years.
Observational Mechanics and Precession
The Sothic cycle is a specific example of two cycles of differing length
interacting to cycle together, here called a tertiary cycle. This is
mathematically defined by the formula 1/a + 1/b = 1/t or half the harmonic mean.
In the case of the Sothic cycle the two cycles are a 365d Egyptian calendar year
and a “Sothic” year. Other tertiary cycles occur with turn signals on two
different cars, two pumps filling a swimming pool, or the hands on an analog
clock passing each other. It is the time required for a faster car to get one
lap ahead of a slower car traveling on a race track.
The Sothic year is the length of time for the star Sirius/Sothis to visually
return to the same position in relation to the sun. Star years measured in this
way vary due to precession, the movement of the Earth’s axis in relation to the
sun. The length of time for a star to make a yearly path can be marked when it
rises to a defined altitude above a local horizon at the time of sunrise. This
altitude does not have to be the altitude of first possible visibility.
Throughout the year the star will rise approximately four minutes earlier each
successive sunrise. Eventually the star will return to its same relative
location at sunrise. This length of time can be called an observational year.
Stars that reside close to the ecliptic or the ecliptic meridian will on
average exhibit observational years close to the sidereal year of 365.2564d. The
ecliptic and the meridian cut the sky into four quadrants. The axis of the earth
wobbles around slowly moving the observer and changing the observation of the
event. If the axis swings the observer closer to the event its observational
year will be shortened. Likewise, the observational year can be lengthened when
the axis swings away from the observer. This depends upon which quadrant of the
sky the phenomenon is observed.
The Sothic year is remarkable because its average duration was exactly
365.25d in the early 4th millennium BC before the unification of Egypt.
The slow rate of change from this value is also of note. If observations and
records could have been maintained during predynastic times the Sothic rise
would optimally return to the same calendar day after 1461 calendar years. This
value would drop to about 1456 calendar years by the Middle Kingdom. The 1461
value could also be maintained if the date of the Sothic rise were artificially
maintained by moving the feast in celebration of this event one day every fourth
year instead of rarely adjusting it according to observation.
It has been noticed, and the Sothic cycle confirms, that Sirius does not move
retrograde across the sky like other stars, a phenomenon widely known as the
precession of the equinox. Professor
Jed Buchwald
wrote “Sirius remains about the
same distance from the equinoxes – and so from the solstices – throughout these
many centuries, despite precession.” For the same reason, the helical
rising (or zenith) of Sirius does not slip through the calendar (at the
precession rate of about one day per 71.6 years), as other stars do. This
remarkable stability within the solar year may be one reason that the Egyptians
used it as a basis for their calendar whereas no other star would have sufficed.
The lunisolar theory of precession requires that the earth wobble enough to
lose one complete rotation on its axis and one revolution around the sun
(relative to the fixed stars) per precession cycle. Modern astronomers now
measure the rate of precession via radio telescopes fixed on distant quasars and
a process known as Very Long Baseline Interferometry (VLBI) confirms the earth
changes orientation to the stars at about 50.3 arc seconds per year, equating to
one complete precession of the equinox in about 25,700 years. Nonetheless,
Sirius, due to its proper motion, remains practically stationary making it the
ideal marker for ancient Egyptian planning purposes.
Problems and
criticisms
Determining the date of a heliacal rise of Sothis has been shown to be
difficult, especially considering the need to know the exact latitude of the
observation. Another problem is that because the Egyptian calendar loses one day
every four years, a heliacal rise will take place on the same day for four years
in a row, and any observation of that rise can date to any of those four years,
making the observation not extremely precise.
A number of criticisms have been leveled against the reliability of dating by
the Sothic cycle. Some are serious enough to be considered problematic. Firstly,
none of the astronomical observations have dates that mention the specific
pharaoh in whose reign they were observed, forcing Egyptologists to supply that
information on the basis of a certain amount of informed speculation. Secondly
there is no information regarding the nature of the civil calendar throughout
the course of Egyptian history, forcing Egyptologists to assume that it existed
unchanged for thousands of years; the Egyptians would only have needed to carry
out one calendar reform in a few thousand years for these calculations to be
worthless. Other criticisms are not considered as problematic, e.g. there is no
extant mention of the Sothic cycle in ancient Egyptian writing, which may simply
be a result of it either being so obvious to Egyptians that it didn’t merit
mention or to relevant texts being destroyed over time or still awaiting
discovery.
Some have recently claimed that the
Theran eruption
marks the beginning of the
Eighteenth dynasty
due to Theran ash and pumice
discoveries in the ruins of
Avaris
in layers that mark the end of the
Hyksos era[citation
needed]. Because the evidence of
dendrochronologists
indicates the eruption took
place in 1626 BC, this has been taken to indicate that dating by the Sothic
cycle is off by 50–80 years at the outset of the 18th dynasty[citation
needed]. Claims that the Thera eruption is the
subject of the
Tempest Stele
of
Ahmose I
have been disputed by writers such as
Peter James
.
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